Objectives: To determine nationally representative estimates of the incidence of stroke and intracranial venous thrombosis during pregnancy and the puerperium, and to identify potential risk factors for these conditions.
Methods: National Hospital Discharge Survey data were analyzed for the period 1979 to 1991. Nationally representative estimates of risk were calculated by age, race, presence of pregnancy-related hypertension, census region, hospital ownership, and number of hospital beds. Multivariate models were developed using logistic regression.
Results: There were an estimated 8,918 cases of stroke and 5,723 cases of intracranial venous thrombosis during pregnancy and the puerperium in the United States among 50,264,631 deliveries, giving risks of 17.7 cases of stroke and 11.4 cases of intracranial venous thrombosis per 100,000 deliveries. In the multivariate models, stroke was associated strongly with pregnancy-related hypertension, larger hospital size, and proprietary hospital ownership, and inversely associated with living in the South. Intracranial venous thrombosis was associated with maternal age.
Conclusions: Stroke and intracranial venous thrombosis are relatively common complications of pregnancy and the puerperium. Collectively, rates for these conditions are about 50% greater for the entire period of pregnancy and the puerperium than for the immediate peripartum period.